Field of the Invention
The invention relates to apparatus for measuring mass throughput of a fluid which is being moved in a channel by a processing machine, wherein the term "processing machine" is meant to include such equipment generally referred to as pumps which are used for circulating liquids as well as blowers which are used for circulating gases. In principle, the apparatus of the instant application and the method of operation thereof are applicable to all types of fluids and to a multiplicity of machines or installations, but the invention is described hereinafter with respect to a specific practical application and, more particularly, by way of example, with respect to a gas-cooled high-temperature nuclear reactor such as has been described, for example, in European Pat. No. (EP-B) 0 036 166.
One of the most important values or parameters which is used for monitoring and controlling such a reactor (as well as many other systems) is the mass throughput of the coolant. If conventional measuring devices are used for this purpose, suitable orifices or restrictors, for example, must be arranged in the fluid stream or flow which cause an additional pressure loss, or relatively long inlet and outlet sections are required which are located upstream of and downstream of the measuring equipment; the realization of such devices in the aforementioned nuclear reactor has not been possible heretofore, taking into consideration desired efficiency, accessibility and crowded spatial conditions.
It is accordingly an object of the invention to provide an apparatus for measuring mass throughput of a fluid which is being moved in a channel without having to resort to such aids and which can also be used without alteration for different system pressures.
It is further an object of the invention, in the specific case of the aforementioned high-temperature nuclear reactor, to provide such apparatus which permits the greatest possible use to be made of measuring devices which are already available for other reasons, so that it is possible to limit the additional expense to that for providing a circuit for evaluating measurement values which are already available.